Ronnie was my choice, but I think you should've added at least McMichael, LJ Shelton and Harrington to the list, and maybe even Beasley.
Tight ends can be offensive MVPs for teams (Gates, Shockey, Heap, Crumpler, etc.).
Blind-side tackles are extremely important, and even more so when they are protecting a QB coming off of a MAJOR knee injury.
As for Harrington, if Culpepper goes down early in the season (which I definitely don't want to happen, but there's a good chance), then he'll have to guide the team.